Pluggable modules may support different types of cable links, such as fiber and copper links. Typically, a pluggable module includes a shell housing that encloses (houses) a transceiver module for a specific type of link. A cable is inserted into one end of the pluggable module to connect with the transceiver module housed within it, and an opening at an opposite end of the pluggable module exposes interface contacts of the housed transceiver module. When a pluggable module is inserted into a (module-receiving) cage, the exposed interface contacts of the housed transceiver module engage with coupling circuitry within the cage. The cage provides interface circuitry for coupling the housed transceiver module to backplane circuitry.
Pluggable modules may be used in high-speed input/output (I/O) interconnections. Different transceiver modules may also have different speed and voltage operating requirements, which place different power and heat requirements on the pluggable modules that house the transceiver modules.